09.95
Siemens AG 2001 All Rights Reserved 6FC5197–jAA50 3-9
SINUMERIK 840C (IA)
3.5.2 System initialization program
After the self diagnostics program has been run through, the system initialization
program is requested.
In its first section, the data required for running the organization program are set
up. This setting up includes:
SStack organization,
SSegmentation for word processor and co-processor,
SEntries in the location dependent CPU interrupt table,
STask priority lists,
SSetting up task data,
SInitialization of counts and periodic values.
In the second section the system initialization program defines the type of start up
after switching on the mains voltage. The following points are checked:
SWhether the switch-on test pattern is missing (i.e. data lost)
SWhether there is a battery interrupt
SIf the setting-up bit is set
SRequest from the NC “automatic warm restart after setting-up overall reset”
SSTOZUS operating status bit set (acquisition of interupt event or continuation
of the STOP state, see Section 8)
SCold restart or warm restart attempt aborted.
If the STOZUS identifier is set, the control remains in the STOP state.
If, in the second section, (testing of run-up after switching on the mains voltage)
the STOZUS identifier is not set, but one of the other conditions is fulfilled, an au-
tomatic cold restart is executed; a warm restart of the control only occurs if none
of the mentioned conditions are fulfilled.
Overall reset with subsequent bootstrapping of the user memory (ORLOE = 1) is
always required
SIf first setting up is instigated,
SData loss has occurred by removing the PLC CPU or, in the case of power
failure, due to simultaneous battery voltage failure.
SAfter forced boot (SW 3 and higher)
If the mains voltage fails during active processing checks, the processing checks
are aborted by the programmer. The system initialization program instigates the
cold restart.
3 PLC Installation
3.5.2 System initialization program